Hi Bea and thanks for a quick response!
I was looking through the forum for the possible solution for the problem with N26's IBAN. It starts with DE and it is, of course, conforms with the German IBAN format. I'm trying to buy a tariff, system simply refuses to verify my IBAN and I couldn't proceed.
Problem seems the same as in Congstar doesn’t accept IBAN - meincongstar - congstar Support Forum that case. However how it was solved seems unclear to me.
Could anyone help on above?